Ottawa was built as two cities glued together. Upper Town on the bluff for the officer class. Lower Town on the riverbank for the French and Irish Catholic workers who built the canal. Two hundred years later the class line in the street grid is still legible, and this corridor walks it stop by stop.
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Plaza Bridge: The Seam

The line between Upper Town and Lower Town. Sappers' Bridge stood here from 1827 until its demolition on 23 July 1912, then Plaza Bridge replaced it in December of that year. The seam did not move.

The unified French-and-Irish-Catholic parish of Lower Town from 1832 through 1888. Antoine Robillard's 1841 neoclassical start, Father Pierre-Adrien Telmon's 1844 Gothic Revival redesign, Father Damase Dandurand's 1866 twin spires.

Colonel John By built the first market here in 1827 with one hundred and sixty pounds of Lower Town property-rent revenue. The market has operated on the same site continuously since. Designated a Heritage Conservation District on 6 February 1991.

Honoré Foisy's early-1900s tinsmith-shop facade from 136 Guigues Avenue. The original house was condemned by 1961; the NCC salvaged the facade; sculptor Arthur 'Art' Price restored the metalwork in 1973.

On 3 August 1890, the Irish Catholic congregation of Lower Town opened its own church at 314 Saint Patrick Street, four blocks east of Notre-Dame Basilica. The split had been negotiated in March 1888 with Archbishop Joseph-Thomas Duhamel. This is the climax stop.

The bluff above the canal entry-flight, where the canal officer class lived. Named for Major Daniel Bolton, Royal Engineers, who succeeded John By in command of the Rideau Canal works after By's 1832 recall.

The oldest stone building in Ottawa. Built in 1827 by stonemason Thomas Mackay for Colonel By as the Rideau Canal construction depot. Three storeys, 2.5-foot-thick limestone walls, Georgian masonry. Museum since 1951.

The modern dividing line. A residential street widened to six lanes in the mid-twentieth century as a planned arterial to the Macdonald-Cartier Bridge, which opened in 1965. The widening cut Lower Town in half. The corridor is restated.
Weekday mid-morning, Tuesday through Thursday, between nine and noon. Plaza Bridge and the ByWard Market fill with tour buses and lunch-hour foot traffic from late morning through mid-afternoon in summer. The corridor is quieter on weekday mornings in shoulder season (May, early June, late September, October). Saturdays and Sundays during market season are the most crowded; the audio works at those times but pause-stops at the market are tight. Winter walks the corridor with almost no crowds; the path down to the Bytown Museum from Major's Hill Park is icy from December through March, and the Commissariat exterior is the audio anchor when the museum is closed.
Go deeper on what you'll see, hear, and walk through.